Electric glowlamp and its manufacture



Aug. 11, 1925. 1,549,476

K. FINCKH ELECTRIC GLQWLAMP AND ITS MANUFACTURE 7 Filed Sept. *7, 1921 ZSheetS-Sheei. 1

Aug. 11, 1925.

K. FINCKH ELECTRIC GLOWLAMP AND ITS MANUFACTURE Filed. Se t; '7, 1921 2 Shoots-Sheet 2 Fig.3

Patented Aug. 11, 1925..

UNETED STATES KARL FINCKH, 0F IBERLIN-TEMPELHOF, GERMANY, ASSIGNOR, BY MESNE ASSIGLF MEETS, T0 GENERAL ELECTRIC COMPANY, OF SCHENECTADY, NEW YORK, A. GOR- PORATION OF NEW YORK.

ELECTRIC GLO'WLAMP AND ITS MANUFAGTURE.

Application filed September 7, 1921. Serial No. 499,042.

To all whom it may concern: 7

Be it'known that I, FINoKH, a philosophical doctor, chemist, residing at Hohenzollernkorso 16, Berlin-Tempelhof, Germany, have invented certain new. and useful Improvements in Electric Glowlamps and Their Manufacture, of which the following is a specification.

This invention relates to electric glowlamps and methods and devices for their manufacture.

Electric glowlamps are known in which a short pumping orv air extraction tube is drawn out from't-he material of which the wall or globe of the lamp consists (more particularly from the flanged foot pipe, i.e.

the flanged pipe, at the foot of the lamp) by means of a tube-drawing member in the shape of a spike which is driven into the side of the glass tube after it has been softened byx h eating. The procedure adopted hitherto'has been to form a small tube by means of a spike and to subsequently detach by a special operation the closed end or point of this tube so as to obtain the opening required for the evacuation of the lamp:

The object of the present invention is to considerably simplify this method of manufacture and this is accomplished by using the contrivance that is employed for forming the small evacuation or pumping tube for the additional function of opening or piercing the point of the spike by means of which the said small tube is drawn, is furnished with a channel extending throughout its central axis and connected to a supply of compressed air whiclu, on the spike being driven into the glassflis automatically turned on sothat pressure is applied in the interior of the small tube. At the same time the air supply of a blowpipe flame is opened which softens the point of the small tube sufficiently to enable it to be pierced by the said air pressure. When lamps are manufactured in accordance with the novel process the operation of closing the hole in the evacuation tube by fusing the glass after the evacuation is completed is facilitated, be-

this tube. To this end cause the or rough.

A constructional form of a device for carrying out the. process in accordance with the invention, is shown in the drawing, in which Fig. 1 is a tube holder,

Fig. 2 is aside view of Fig. 1,

lg. 3 is a view of a modified device in which a shield is provided that cooperates with the hollow tube-drawing spike, and

Fig. 4 illustrates a device for dealing with a plurality of lamps or flanged foottubes which are inserted in the device simultaneously. I

In the drawings, instead of the entire glowlamp, only thefso-called flanged foottube a is shownon 'Which the supporting frame of the luminous body is supported. The flange Z) serves to connect the foot-tube to the rim of the lower opening of the lamp globe. The'flanged foot-tube is held in a rotating clip a. The flame d of a blowlamp serves to heat up the zone of the foot-tube, in which the evacuation tube e is to be subsequently formed. The clip 0 with the a is adapted to be rotated plan view of a device with one flanged foot-tube by means of a pulley f.

The flame g of a second blowlamp or torch serves to heat the particular spot of the foot-tube a from which the small evacuation tube e is to be formed. This flame becomes eflective after the rotation of the foot-tube is stopped,

Adjacent to the foot-tube a is a spike 72, which is adapted to be swung round on a hollow pivot 11 that acts as a conduit for compressed air. The spike it has a central longitudinal passage and a handle is by which it can be swung round. The central passage l in the spike it extends to the hollow pivot z and. is adapted to communicate with the bore of this pivot e by way of a transverse port m in the same whenever the spike It is rocked into the operating posi tion indicated by the spike h is thus rocked the small evacuation tube e is drawn from the heated and PATENT oFFieE.

dash-and-dot lines. When softened material of the wall of the foottube a. At the same time a connection is eflected through a passage 11, in the hub of the spike it between the transverse port 0 in the pivot 11 and a pipe p which leads to a third blowpipe flame g.

The above-described device is operated in the following manner: First the clip 0 is caused to rotate with the tube a, and the flame d is applied to the latter until it is sufliciently preheated. Then the motion of the tube 'a is stopped and the flame g becomes eifective and softens the particular part of the tube at which the spike is to be driven in. When this part has become soft enough the'spike h is swung round by means of the handle is. At the same time the compressedair takes effect in the interior of the drawn tube in the manner already 'described. Shortly before the spike reaches its final inner position the third blowpipe flame g commences acting on the point of the drawn tube 6 so that this point softens and the compressed air is enabled to burst through it. By this means it is possible to produce lamps with evacuation tubes at a rapid rate, and at the same time to avoid the occurrence of faulty products.

To obtain a more effective cooling of the spike h the arrangement may be such that at the moment the spike it has been turned back into its normal position compressed air flows out of it. This may be easily accomplished as illustrated in Fig. 3 by means of a suitable located vent a in the wall of the hollow pivot i. With this arrangement provision must be made to prevent the air-jet expelled from the spike h from impinging upon the heated foot-tube a. This provision may consist in a movable screen or shield 8 arranged adjacent to the clip 0 and adapted to be moved before the point of the spike h when this spike regains its normal position, but to be moved out of the path of the spike h when it is purpose of forming an evacuation tube in the wall of the foot-tube. Th screen 8 is guided by guide-members s and connected through the medium of a bell-crank lever t to a lateral arm to projecting from the spike h. lVhen the latter is swung forward the bell-crank lever is moved into the position indicated by b-rokenlincs and the screen 8 is thereby shifted upward out of the path of the spik h.

As diagrammatically illustrated in Fig. 4 it is also possible to fix a plurality (say 8) of flanged foot-tubes in a circle, equidistant clips (not shown) being provided for this purpose which are mounted on a common rotary support such asa disk 0. The disk is rotated step-by-step which may be accomplished by means of a ratchet wheel w and a handle a: with a propelling pawl w. At each step one of the said clips and thus a swung forward for the foot-tube a, is shifted into the range of the blowpipe flames -(not shown) and into the path of the spike h. The extent of the rotary movement of the handle as is determined by the stops y, y. The pawl to that engages with the ratchet wheel is urged inward by a spring 10 so that it glides from the tooth that has been moved round to the next tooth of the wheel to when the handle is moved back by the spring a into its initial position. The cooling air admitted into the spike h is preferably controlled in such a manner that it only emerges from the spike h when the heated evacuation tube has been moved out of the range of the air-jet. A simple controlling gear for accomplishing this may be obtained by connecting a cock .2 in a special cooling air pipe 2 to the handle as by means of a connecting rod 2 in such a way that, immediately after the foottube a is moved out of the position in which its evacuation tube is formed, the cooling air is admitted, the flow of this air being stopped, however, before the next foot-tube reac es the position in which it is operated on. Thus the cock 2 is only kept open during the time that the handle it is swung round. The compressed air, which bursts through, and thus opens, the point of the evacuation tube formed when the spike IL is rocket inward, is introduced through a special compressed air pipe h which, as in the case of Figs. 1 and 2, is also made to communicate with the air passage in the spike only when the latter is swung inward.

By obvious changes of the above-describedarrangement the novel process may also be applied in cases in which th evacuation tube, instead of being located in the flanged foot-tube, is situated at some other part of the wall orglobe of the lamp.

I claim:

1. In anarrangement for drawing a tube from the material of the wall of a glowlamp, means for softening the said material, a tube-drawing tool consisting of a hollow spike adapted to be driven into the softened material and to draw atube therefrom, and a conduit for supplying compressed air to the hollow of th said spike.

2. In an arrangement for drawing a tube from the material of the wall of a glowlamp, means for softening the said material, a tube-drawing tool consisting of a hollow spike adapted to be driven into the softened material, a hollow pivot for the said spike, a hub surrounding the said pivot and joined to the said spike, passages in the hollow pivot and the hub for efiec'ting a connection between the hollow in the pivot and the hollow in the spike when'it is driven into the said material, and a compressed air supply connected to the hollow of the said pivot.

3. In an arrangement for drawing a tube from the material of the wall of a glowlamp, means for softening the said. material, a tube-drawing tool consisting of a hollow spike adapted to be driven into the softening material, a hollow pivot for the said spike, a hub surrounding the said pivot and joined to the said s ike, passages in the hollow pivot and the hub for effecting a connection between the hollow in the pivot and the hollow in the spike when it is driven into the said material, a compressed air supply connected to the hollow of the said pivot, a blowpipe for directing a flame against the end of the said drawn tube and for thus softening the said end, and passages in the hollow pivot and the said hub for effecting a connection between the hollow of the pivot and the said blowpipe when the spike is operated.

4,. In an arrangement for drawing a tube from the material of the wall of a glowlamp, means for softening the said material, a tube-drawing tool consisting of a hollow spike adapted to be driven into the softened material, a hollow pivot for the said spike, a hub surrounding the said pivot and joined to the said spike, passages in the hollow pivot and the hub for efi'ecting a connection between the hollow in the pivot and the hollow in spike when it is driven into the said material, a compressed air supply connected to the hollow of the said pivot, a blowpi e fer directing a flame again-st the end of t 1e said drawn tube and for thus softening the said end, passages in the hollow pivot and the said hub for eifecting a connection between the hollow of the pivot and the said blowpipe when the spike is operated, and passages for conducting cooling air through the spike when it is returned to its normal position g 5., In an arrangement for drawing a tube from the material of the wall of a glowlamp, means for softening the said material, a tube-drawing tool consisting of a hollow spike adapted tobe driven into the softenedmaterial, a hollow pivot for the said spike, a hub surrounding the said pivot and joined to the said spike, passages in the hollow pivot and the hub for efiecting a connection between the hollow in the pivot and the hollow in the spike when it is driven into the said material, a compressed air supply connected to the hollow of the said pivot, a blowpipe for directing a flame against the end of the said drawn tube and "for thus softening the said end, passages in the hollow pivot and the said hub for effecting a connection between the hollow of the pivot and the said blowpipe when the spike is 0perated,- passages for conducting cooling air through the spike when it is returned to its normal position, and means for diverting the cooling air from the said material from which the evacuation tube is formed.

6. In a glass forming device, in combination a blow torch for heating a glass body, a drawing tool for drawing the glass when heated, said tool movably mounted within range of the glass body for projecting into and thereby drawing the glass and provided with an air passage whereby when connected with a source of compressed air, the glass may also be blown through the tool while the glass is hot,

7. In a combined glass forming and drawing device, means for holding a-glass bod. in place, means vfor heating the body while in place and a combined blowing anddrawing tool movablyv mounted within range of the glass whereby the glass may be drawn by and blown through the tool.

8. The process of preparing a duct tube at the side of a glass body which consists in heating a limited area oi the body and then raising the temperature of a spot inthe heated area until the spot becomes plastic and then drawing the plastic material to heating a general area of the body and then raising the temperature of a spot in the heated area until the spot becomes plastic and then drawing the plastic material to form a tube and thereafter heating the tube formed and blowing to puncture the tube.

10. lin a glass drawing and blowing machine, a heater, a rotatable glass holder for holding and rotating glassware in proximity of said heater, whereby the, glass may be heated generally, a second heater for heating a spot in the heated area of the glass to renderthe spot plastic when the holder is stationary and a mandrel movably mounted adjacent said holder adapted to engage and draw the plastic material into a tubular projection, said mandrel provided with a duct for blowing the projection to produce a puncture therein.

11. In a glass drawing and blowing machine, a heater, a rotatable glass holder for holding and rotating glassware in proximity of said heater, whereby the glass may be heated generally, a second heater for heating a spot in the heated area of the glass to render the spot plastic when the holder is stationary and a mandrel movably mounted adjacent said holder adapted to engage and draw the plastic material into a tubular projection, said mandrel provided with a duct for blowing the projection to puncture the projection.

12. In a glass drawing and blowing machine, a: heater, a rotatable glass holder for holding and rotating glassware in proximity of said heater, whereby the glass may be heated generally, a second heater for heating a spot in the heated area of the glass to render the spot plastic when the holder operation to cause the projection to he puncis stationary and a mandrel movably tured. 10 mounted adjacent said holder adapted to en- In t stim0ny Wh r Of affix my signagage and draw the plastic material into a l 1 the Presence Of'tWO Witnessestubular projection, said mandrel provided DR. KARL FINCKH.

with a duct for blowing the projection, and Witnesses I a third heating device for maintaining the WILLY WILDE, projection heated during the blowing i FREDEmG VON MIDA. 

